1 /**
2  * Microchip ENCX24J600 ethernet driver
3  *
4  * Copyright (C) 2015 Gridpoint
5  * Author: Jon Ringle <jringle@gridpoint.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  */
13 
14 #include <linux/device.h>
15 #include <linux/errno.h>
16 #include <linux/etherdevice.h>
17 #include <linux/ethtool.h>
18 #include <linux/interrupt.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/netdevice.h>
22 #include <linux/regmap.h>
23 #include <linux/skbuff.h>
24 #include <linux/spi/spi.h>
25 
26 #include "encx24j600_hw.h"
27 
28 #define DRV_NAME	"encx24j600"
29 #define DRV_VERSION	"1.0"
30 
31 #define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
32 static int debug = -1;
33 module_param(debug, int, 0000);
34 MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");
35 
36 /* SRAM memory layout:
37  *
38  * 0x0000-0x05ff TX buffers  1.5KB  (1*1536) reside in the GP area in SRAM
39  * 0x0600-0x5fff RX buffers 22.5KB (15*1536) reside in the RX area in SRAM
40  */
41 #define ENC_TX_BUF_START 0x0000U
42 #define ENC_RX_BUF_START 0x0600U
43 #define ENC_RX_BUF_END   0x5fffU
44 #define ENC_SRAM_SIZE    0x6000U
45 
46 enum {
47 	RXFILTER_NORMAL,
48 	RXFILTER_MULTI,
49 	RXFILTER_PROMISC
50 };
51 
52 struct encx24j600_priv {
53 	struct net_device        *ndev;
54 	struct mutex              lock; /* device access lock */
55 	struct encx24j600_context ctx;
56 	struct sk_buff           *tx_skb;
57 	struct task_struct       *kworker_task;
58 	struct kthread_worker     kworker;
59 	struct kthread_work       tx_work;
60 	struct kthread_work       setrx_work;
61 	u16                       next_packet;
62 	bool                      hw_enabled;
63 	bool                      full_duplex;
64 	bool                      autoneg;
65 	u16                       speed;
66 	int                       rxfilter;
67 	u32                       msg_enable;
68 };
69 
70 static void dump_packet(const char *msg, int len, const char *data)
71 {
72 	pr_debug(DRV_NAME ": %s - packet len:%d\n", msg, len);
73 	print_hex_dump_bytes("pk data: ", DUMP_PREFIX_OFFSET, data, len);
74 }
75 
76 static void encx24j600_dump_rsv(struct encx24j600_priv *priv, const char *msg,
77 				struct rsv *rsv)
78 {
79 	struct net_device *dev = priv->ndev;
80 
81 	netdev_info(dev, "RX packet Len:%d\n", rsv->len);
82 	netdev_dbg(dev, "%s - NextPk: 0x%04x\n", msg,
83 		   rsv->next_packet);
84 	netdev_dbg(dev, "RxOK: %d, DribbleNibble: %d\n",
85 		   RSV_GETBIT(rsv->rxstat, RSV_RXOK),
86 		   RSV_GETBIT(rsv->rxstat, RSV_DRIBBLENIBBLE));
87 	netdev_dbg(dev, "CRCErr:%d, LenChkErr: %d, LenOutOfRange: %d\n",
88 		   RSV_GETBIT(rsv->rxstat, RSV_CRCERROR),
89 		   RSV_GETBIT(rsv->rxstat, RSV_LENCHECKERR),
90 		   RSV_GETBIT(rsv->rxstat, RSV_LENOUTOFRANGE));
91 	netdev_dbg(dev, "Multicast: %d, Broadcast: %d, LongDropEvent: %d, CarrierEvent: %d\n",
92 		   RSV_GETBIT(rsv->rxstat, RSV_RXMULTICAST),
93 		   RSV_GETBIT(rsv->rxstat, RSV_RXBROADCAST),
94 		   RSV_GETBIT(rsv->rxstat, RSV_RXLONGEVDROPEV),
95 		   RSV_GETBIT(rsv->rxstat, RSV_CARRIEREV));
96 	netdev_dbg(dev, "ControlFrame: %d, PauseFrame: %d, UnknownOp: %d, VLanTagFrame: %d\n",
97 		   RSV_GETBIT(rsv->rxstat, RSV_RXCONTROLFRAME),
98 		   RSV_GETBIT(rsv->rxstat, RSV_RXPAUSEFRAME),
99 		   RSV_GETBIT(rsv->rxstat, RSV_RXUNKNOWNOPCODE),
100 		   RSV_GETBIT(rsv->rxstat, RSV_RXTYPEVLAN));
101 }
102 
103 static u16 encx24j600_read_reg(struct encx24j600_priv *priv, u8 reg)
104 {
105 	struct net_device *dev = priv->ndev;
106 	unsigned int val = 0;
107 	int ret = regmap_read(priv->ctx.regmap, reg, &val);
108 
109 	if (unlikely(ret))
110 		netif_err(priv, drv, dev, "%s: error %d reading reg %02x\n",
111 			  __func__, ret, reg);
112 	return val;
113 }
114 
115 static void encx24j600_write_reg(struct encx24j600_priv *priv, u8 reg, u16 val)
116 {
117 	struct net_device *dev = priv->ndev;
118 	int ret = regmap_write(priv->ctx.regmap, reg, val);
119 
120 	if (unlikely(ret))
121 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
122 			  __func__, ret, reg, val);
123 }
124 
125 static void encx24j600_update_reg(struct encx24j600_priv *priv, u8 reg,
126 				  u16 mask, u16 val)
127 {
128 	struct net_device *dev = priv->ndev;
129 	int ret = regmap_update_bits(priv->ctx.regmap, reg, mask, val);
130 
131 	if (unlikely(ret))
132 		netif_err(priv, drv, dev, "%s: error %d updating reg %02x=%04x~%04x\n",
133 			  __func__, ret, reg, val, mask);
134 }
135 
136 static u16 encx24j600_read_phy(struct encx24j600_priv *priv, u8 reg)
137 {
138 	struct net_device *dev = priv->ndev;
139 	unsigned int val = 0;
140 	int ret = regmap_read(priv->ctx.phymap, reg, &val);
141 
142 	if (unlikely(ret))
143 		netif_err(priv, drv, dev, "%s: error %d reading %02x\n",
144 			  __func__, ret, reg);
145 	return val;
146 }
147 
148 static void encx24j600_write_phy(struct encx24j600_priv *priv, u8 reg, u16 val)
149 {
150 	struct net_device *dev = priv->ndev;
151 	int ret = regmap_write(priv->ctx.phymap, reg, val);
152 
153 	if (unlikely(ret))
154 		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
155 			  __func__, ret, reg, val);
156 }
157 
158 static void encx24j600_clr_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
159 {
160 	encx24j600_update_reg(priv, reg, mask, 0);
161 }
162 
163 static void encx24j600_set_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
164 {
165 	encx24j600_update_reg(priv, reg, mask, mask);
166 }
167 
168 static void encx24j600_cmd(struct encx24j600_priv *priv, u8 cmd)
169 {
170 	struct net_device *dev = priv->ndev;
171 	int ret = regmap_write(priv->ctx.regmap, cmd, 0);
172 
173 	if (unlikely(ret))
174 		netif_err(priv, drv, dev, "%s: error %d with cmd %02x\n",
175 			  __func__, ret, cmd);
176 }
177 
178 static int encx24j600_raw_read(struct encx24j600_priv *priv, u8 reg, u8 *data,
179 			       size_t count)
180 {
181 	int ret;
182 
183 	mutex_lock(&priv->ctx.mutex);
184 	ret = regmap_encx24j600_spi_read(&priv->ctx, reg, data, count);
185 	mutex_unlock(&priv->ctx.mutex);
186 
187 	return ret;
188 }
189 
190 static int encx24j600_raw_write(struct encx24j600_priv *priv, u8 reg,
191 				const u8 *data, size_t count)
192 {
193 	int ret;
194 
195 	mutex_lock(&priv->ctx.mutex);
196 	ret = regmap_encx24j600_spi_write(&priv->ctx, reg, data, count);
197 	mutex_unlock(&priv->ctx.mutex);
198 
199 	return ret;
200 }
201 
202 static void encx24j600_update_phcon1(struct encx24j600_priv *priv)
203 {
204 	u16 phcon1 = encx24j600_read_phy(priv, PHCON1);
205 
206 	if (priv->autoneg == AUTONEG_ENABLE) {
207 		phcon1 |= ANEN | RENEG;
208 	} else {
209 		phcon1 &= ~ANEN;
210 		if (priv->speed == SPEED_100)
211 			phcon1 |= SPD100;
212 		else
213 			phcon1 &= ~SPD100;
214 
215 		if (priv->full_duplex)
216 			phcon1 |= PFULDPX;
217 		else
218 			phcon1 &= ~PFULDPX;
219 	}
220 	encx24j600_write_phy(priv, PHCON1, phcon1);
221 }
222 
223 /* Waits for autonegotiation to complete. */
224 static int encx24j600_wait_for_autoneg(struct encx24j600_priv *priv)
225 {
226 	struct net_device *dev = priv->ndev;
227 	unsigned long timeout = jiffies + msecs_to_jiffies(2000);
228 	u16 phstat1;
229 	u16 estat;
230 	int ret = 0;
231 
232 	phstat1 = encx24j600_read_phy(priv, PHSTAT1);
233 	while ((phstat1 & ANDONE) == 0) {
234 		if (time_after(jiffies, timeout)) {
235 			u16 phstat3;
236 
237 			netif_notice(priv, drv, dev, "timeout waiting for autoneg done\n");
238 
239 			priv->autoneg = AUTONEG_DISABLE;
240 			phstat3 = encx24j600_read_phy(priv, PHSTAT3);
241 			priv->speed = (phstat3 & PHY3SPD100)
242 				      ? SPEED_100 : SPEED_10;
243 			priv->full_duplex = (phstat3 & PHY3DPX) ? 1 : 0;
244 			encx24j600_update_phcon1(priv);
245 			netif_notice(priv, drv, dev, "Using parallel detection: %s/%s",
246 				     priv->speed == SPEED_100 ? "100" : "10",
247 				     priv->full_duplex ? "Full" : "Half");
248 
249 			return -ETIMEDOUT;
250 		}
251 		cpu_relax();
252 		phstat1 = encx24j600_read_phy(priv, PHSTAT1);
253 	}
254 
255 	estat = encx24j600_read_reg(priv, ESTAT);
256 	if (estat & PHYDPX) {
257 		encx24j600_set_bits(priv, MACON2, FULDPX);
258 		encx24j600_write_reg(priv, MABBIPG, 0x15);
259 	} else {
260 		encx24j600_clr_bits(priv, MACON2, FULDPX);
261 		encx24j600_write_reg(priv, MABBIPG, 0x12);
262 		/* Max retransmittions attempt  */
263 		encx24j600_write_reg(priv, MACLCON, 0x370f);
264 	}
265 
266 	return ret;
267 }
268 
269 /* Access the PHY to determine link status */
270 static void encx24j600_check_link_status(struct encx24j600_priv *priv)
271 {
272 	struct net_device *dev = priv->ndev;
273 	u16 estat;
274 
275 	estat = encx24j600_read_reg(priv, ESTAT);
276 
277 	if (estat & PHYLNK) {
278 		if (priv->autoneg == AUTONEG_ENABLE)
279 			encx24j600_wait_for_autoneg(priv);
280 
281 		netif_carrier_on(dev);
282 		netif_info(priv, ifup, dev, "link up\n");
283 	} else {
284 		netif_info(priv, ifdown, dev, "link down\n");
285 
286 		/* Re-enable autoneg since we won't know what we might be
287 		 * connected to when the link is brought back up again.
288 		 */
289 		priv->autoneg  = AUTONEG_ENABLE;
290 		priv->full_duplex = true;
291 		priv->speed = SPEED_100;
292 		netif_carrier_off(dev);
293 	}
294 }
295 
296 static void encx24j600_int_link_handler(struct encx24j600_priv *priv)
297 {
298 	struct net_device *dev = priv->ndev;
299 
300 	netif_dbg(priv, intr, dev, "%s", __func__);
301 	encx24j600_check_link_status(priv);
302 	encx24j600_clr_bits(priv, EIR, LINKIF);
303 }
304 
305 static void encx24j600_tx_complete(struct encx24j600_priv *priv, bool err)
306 {
307 	struct net_device *dev = priv->ndev;
308 
309 	if (!priv->tx_skb) {
310 		BUG();
311 		return;
312 	}
313 
314 	mutex_lock(&priv->lock);
315 
316 	if (err)
317 		dev->stats.tx_errors++;
318 	else
319 		dev->stats.tx_packets++;
320 
321 	dev->stats.tx_bytes += priv->tx_skb->len;
322 
323 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
324 
325 	netif_dbg(priv, tx_done, dev, "TX Done%s\n", err ? ": Err" : "");
326 
327 	dev_kfree_skb(priv->tx_skb);
328 	priv->tx_skb = NULL;
329 
330 	netif_wake_queue(dev);
331 
332 	mutex_unlock(&priv->lock);
333 }
334 
335 static int encx24j600_receive_packet(struct encx24j600_priv *priv,
336 				     struct rsv *rsv)
337 {
338 	struct net_device *dev = priv->ndev;
339 	struct sk_buff *skb = netdev_alloc_skb(dev, rsv->len + NET_IP_ALIGN);
340 
341 	if (!skb) {
342 		pr_err_ratelimited("RX: OOM: packet dropped\n");
343 		dev->stats.rx_dropped++;
344 		return -ENOMEM;
345 	}
346 	skb_reserve(skb, NET_IP_ALIGN);
347 	encx24j600_raw_read(priv, RRXDATA, skb_put(skb, rsv->len), rsv->len);
348 
349 	if (netif_msg_pktdata(priv))
350 		dump_packet("RX", skb->len, skb->data);
351 
352 	skb->dev = dev;
353 	skb->protocol = eth_type_trans(skb, dev);
354 	skb->ip_summed = CHECKSUM_COMPLETE;
355 
356 	/* Maintain stats */
357 	dev->stats.rx_packets++;
358 	dev->stats.rx_bytes += rsv->len;
359 
360 	netif_rx(skb);
361 
362 	return 0;
363 }
364 
365 static void encx24j600_rx_packets(struct encx24j600_priv *priv, u8 packet_count)
366 {
367 	struct net_device *dev = priv->ndev;
368 
369 	while (packet_count--) {
370 		struct rsv rsv;
371 		u16 newrxtail;
372 
373 		encx24j600_write_reg(priv, ERXRDPT, priv->next_packet);
374 		encx24j600_raw_read(priv, RRXDATA, (u8 *)&rsv, sizeof(rsv));
375 
376 		if (netif_msg_rx_status(priv))
377 			encx24j600_dump_rsv(priv, __func__, &rsv);
378 
379 		if (!RSV_GETBIT(rsv.rxstat, RSV_RXOK) ||
380 		    (rsv.len > MAX_FRAMELEN)) {
381 			netif_err(priv, rx_err, dev, "RX Error %04x\n",
382 				  rsv.rxstat);
383 			dev->stats.rx_errors++;
384 
385 			if (RSV_GETBIT(rsv.rxstat, RSV_CRCERROR))
386 				dev->stats.rx_crc_errors++;
387 			if (RSV_GETBIT(rsv.rxstat, RSV_LENCHECKERR))
388 				dev->stats.rx_frame_errors++;
389 			if (rsv.len > MAX_FRAMELEN)
390 				dev->stats.rx_over_errors++;
391 		} else {
392 			encx24j600_receive_packet(priv, &rsv);
393 		}
394 
395 		priv->next_packet = rsv.next_packet;
396 
397 		newrxtail = priv->next_packet - 2;
398 		if (newrxtail == ENC_RX_BUF_START)
399 			newrxtail = SRAM_SIZE - 2;
400 
401 		encx24j600_cmd(priv, SETPKTDEC);
402 		encx24j600_write_reg(priv, ERXTAIL, newrxtail);
403 	}
404 }
405 
406 static irqreturn_t encx24j600_isr(int irq, void *dev_id)
407 {
408 	struct encx24j600_priv *priv = dev_id;
409 	struct net_device *dev = priv->ndev;
410 	int eir;
411 
412 	/* Clear interrupts */
413 	encx24j600_cmd(priv, CLREIE);
414 
415 	eir = encx24j600_read_reg(priv, EIR);
416 
417 	if (eir & LINKIF)
418 		encx24j600_int_link_handler(priv);
419 
420 	if (eir & TXIF)
421 		encx24j600_tx_complete(priv, false);
422 
423 	if (eir & TXABTIF)
424 		encx24j600_tx_complete(priv, true);
425 
426 	if (eir & RXABTIF) {
427 		if (eir & PCFULIF) {
428 			/* Packet counter is full */
429 			netif_err(priv, rx_err, dev, "Packet counter full\n");
430 		}
431 		dev->stats.rx_dropped++;
432 		encx24j600_clr_bits(priv, EIR, RXABTIF);
433 	}
434 
435 	if (eir & PKTIF) {
436 		u8 packet_count;
437 
438 		mutex_lock(&priv->lock);
439 
440 		packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
441 		while (packet_count) {
442 			encx24j600_rx_packets(priv, packet_count);
443 			packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
444 		}
445 
446 		mutex_unlock(&priv->lock);
447 	}
448 
449 	/* Enable interrupts */
450 	encx24j600_cmd(priv, SETEIE);
451 
452 	return IRQ_HANDLED;
453 }
454 
455 static int encx24j600_soft_reset(struct encx24j600_priv *priv)
456 {
457 	int ret = 0;
458 	int timeout;
459 	u16 eudast;
460 
461 	/* Write and verify a test value to EUDAST */
462 	regcache_cache_bypass(priv->ctx.regmap, true);
463 	timeout = 10;
464 	do {
465 		encx24j600_write_reg(priv, EUDAST, EUDAST_TEST_VAL);
466 		eudast = encx24j600_read_reg(priv, EUDAST);
467 		usleep_range(25, 100);
468 	} while ((eudast != EUDAST_TEST_VAL) && --timeout);
469 	regcache_cache_bypass(priv->ctx.regmap, false);
470 
471 	if (timeout == 0) {
472 		ret = -ETIMEDOUT;
473 		goto err_out;
474 	}
475 
476 	/* Wait for CLKRDY to become set */
477 	timeout = 10;
478 	while (!(encx24j600_read_reg(priv, ESTAT) & CLKRDY) && --timeout)
479 		usleep_range(25, 100);
480 
481 	if (timeout == 0) {
482 		ret = -ETIMEDOUT;
483 		goto err_out;
484 	}
485 
486 	/* Issue a System Reset command */
487 	encx24j600_cmd(priv, SETETHRST);
488 	usleep_range(25, 100);
489 
490 	/* Confirm that EUDAST has 0000h after system reset */
491 	if (encx24j600_read_reg(priv, EUDAST) != 0) {
492 		ret = -EINVAL;
493 		goto err_out;
494 	}
495 
496 	/* Wait for PHY register and status bits to become available */
497 	usleep_range(256, 1000);
498 
499 err_out:
500 	return ret;
501 }
502 
503 static int encx24j600_hw_reset(struct encx24j600_priv *priv)
504 {
505 	int ret;
506 
507 	mutex_lock(&priv->lock);
508 	ret = encx24j600_soft_reset(priv);
509 	mutex_unlock(&priv->lock);
510 
511 	return ret;
512 }
513 
514 static void encx24j600_reset_hw_tx(struct encx24j600_priv *priv)
515 {
516 	encx24j600_set_bits(priv, ECON2, TXRST);
517 	encx24j600_clr_bits(priv, ECON2, TXRST);
518 }
519 
520 static void encx24j600_hw_init_tx(struct encx24j600_priv *priv)
521 {
522 	/* Reset TX */
523 	encx24j600_reset_hw_tx(priv);
524 
525 	/* Clear the TXIF flag if were previously set */
526 	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);
527 
528 	/* Write the Tx Buffer pointer */
529 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
530 }
531 
532 static void encx24j600_hw_init_rx(struct encx24j600_priv *priv)
533 {
534 	encx24j600_cmd(priv, DISABLERX);
535 
536 	/* Set up RX packet start address in the SRAM */
537 	encx24j600_write_reg(priv, ERXST, ENC_RX_BUF_START);
538 
539 	/* Preload the RX Data pointer to the beginning of the RX area */
540 	encx24j600_write_reg(priv, ERXRDPT, ENC_RX_BUF_START);
541 
542 	priv->next_packet = ENC_RX_BUF_START;
543 
544 	/* Set up RX end address in the SRAM */
545 	encx24j600_write_reg(priv, ERXTAIL, ENC_SRAM_SIZE - 2);
546 
547 	/* Reset the  user data pointers    */
548 	encx24j600_write_reg(priv, EUDAST, ENC_SRAM_SIZE);
549 	encx24j600_write_reg(priv, EUDAND, ENC_SRAM_SIZE + 1);
550 
551 	/* Set Max Frame length */
552 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
553 }
554 
555 static void encx24j600_dump_config(struct encx24j600_priv *priv,
556 				   const char *msg)
557 {
558 	pr_info(DRV_NAME ": %s\n", msg);
559 
560 	/* CHIP configuration */
561 	pr_info(DRV_NAME " ECON1:   %04X\n", encx24j600_read_reg(priv, ECON1));
562 	pr_info(DRV_NAME " ECON2:   %04X\n", encx24j600_read_reg(priv, ECON2));
563 	pr_info(DRV_NAME " ERXFCON: %04X\n", encx24j600_read_reg(priv,
564 								 ERXFCON));
565 	pr_info(DRV_NAME " ESTAT:   %04X\n", encx24j600_read_reg(priv, ESTAT));
566 	pr_info(DRV_NAME " EIR:     %04X\n", encx24j600_read_reg(priv, EIR));
567 	pr_info(DRV_NAME " EIDLED:  %04X\n", encx24j600_read_reg(priv, EIDLED));
568 
569 	/* MAC layer configuration */
570 	pr_info(DRV_NAME " MACON1:  %04X\n", encx24j600_read_reg(priv, MACON1));
571 	pr_info(DRV_NAME " MACON2:  %04X\n", encx24j600_read_reg(priv, MACON2));
572 	pr_info(DRV_NAME " MAIPG:   %04X\n", encx24j600_read_reg(priv, MAIPG));
573 	pr_info(DRV_NAME " MACLCON: %04X\n", encx24j600_read_reg(priv,
574 								 MACLCON));
575 	pr_info(DRV_NAME " MABBIPG: %04X\n", encx24j600_read_reg(priv,
576 								 MABBIPG));
577 
578 	/* PHY configuation */
579 	pr_info(DRV_NAME " PHCON1:  %04X\n", encx24j600_read_phy(priv, PHCON1));
580 	pr_info(DRV_NAME " PHCON2:  %04X\n", encx24j600_read_phy(priv, PHCON2));
581 	pr_info(DRV_NAME " PHANA:   %04X\n", encx24j600_read_phy(priv, PHANA));
582 	pr_info(DRV_NAME " PHANLPA: %04X\n", encx24j600_read_phy(priv,
583 								 PHANLPA));
584 	pr_info(DRV_NAME " PHANE:   %04X\n", encx24j600_read_phy(priv, PHANE));
585 	pr_info(DRV_NAME " PHSTAT1: %04X\n", encx24j600_read_phy(priv,
586 								 PHSTAT1));
587 	pr_info(DRV_NAME " PHSTAT2: %04X\n", encx24j600_read_phy(priv,
588 								 PHSTAT2));
589 	pr_info(DRV_NAME " PHSTAT3: %04X\n", encx24j600_read_phy(priv,
590 								 PHSTAT3));
591 }
592 
593 static void encx24j600_set_rxfilter_mode(struct encx24j600_priv *priv)
594 {
595 	switch (priv->rxfilter) {
596 	case RXFILTER_PROMISC:
597 		encx24j600_set_bits(priv, MACON1, PASSALL);
598 		encx24j600_write_reg(priv, ERXFCON, UCEN | MCEN | NOTMEEN);
599 		break;
600 	case RXFILTER_MULTI:
601 		encx24j600_clr_bits(priv, MACON1, PASSALL);
602 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN | MCEN);
603 		break;
604 	case RXFILTER_NORMAL:
605 	default:
606 		encx24j600_clr_bits(priv, MACON1, PASSALL);
607 		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN);
608 		break;
609 	}
610 }
611 
612 static int encx24j600_hw_init(struct encx24j600_priv *priv)
613 {
614 	int ret = 0;
615 	u16 macon2;
616 
617 	priv->hw_enabled = false;
618 
619 	/* PHY Leds: link status,
620 	 * LEDA: Link State + collision events
621 	 * LEDB: Link State + transmit/receive events
622 	 */
623 	encx24j600_update_reg(priv, EIDLED, 0xff00, 0xcb00);
624 
625 	/* Loopback disabled */
626 	encx24j600_write_reg(priv, MACON1, 0x9);
627 
628 	/* interpacket gap value */
629 	encx24j600_write_reg(priv, MAIPG, 0x0c12);
630 
631 	/* Write the auto negotiation pattern */
632 	encx24j600_write_phy(priv, PHANA, PHANA_DEFAULT);
633 
634 	encx24j600_update_phcon1(priv);
635 	encx24j600_check_link_status(priv);
636 
637 	macon2 = MACON2_RSV1 | TXCRCEN | PADCFG0 | PADCFG2 | MACON2_DEFER;
638 	if ((priv->autoneg == AUTONEG_DISABLE) && priv->full_duplex)
639 		macon2 |= FULDPX;
640 
641 	encx24j600_set_bits(priv, MACON2, macon2);
642 
643 	priv->rxfilter = RXFILTER_NORMAL;
644 	encx24j600_set_rxfilter_mode(priv);
645 
646 	/* Program the Maximum frame length */
647 	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
648 
649 	/* Init Tx pointers */
650 	encx24j600_hw_init_tx(priv);
651 
652 	/* Init Rx pointers */
653 	encx24j600_hw_init_rx(priv);
654 
655 	if (netif_msg_hw(priv))
656 		encx24j600_dump_config(priv, "Hw is initialized");
657 
658 	return ret;
659 }
660 
661 static void encx24j600_hw_enable(struct encx24j600_priv *priv)
662 {
663 	/* Clear the interrupt flags in case was set */
664 	encx24j600_clr_bits(priv, EIR, (PCFULIF | RXABTIF | TXABTIF | TXIF |
665 					PKTIF | LINKIF));
666 
667 	/* Enable the interrupts */
668 	encx24j600_write_reg(priv, EIE, (PCFULIE | RXABTIE | TXABTIE | TXIE |
669 					 PKTIE | LINKIE | INTIE));
670 
671 	/* Enable RX */
672 	encx24j600_cmd(priv, ENABLERX);
673 
674 	priv->hw_enabled = true;
675 }
676 
677 static void encx24j600_hw_disable(struct encx24j600_priv *priv)
678 {
679 	/* Disable all interrupts */
680 	encx24j600_write_reg(priv, EIE, 0);
681 
682 	/* Disable RX */
683 	encx24j600_cmd(priv, DISABLERX);
684 
685 	priv->hw_enabled = false;
686 }
687 
688 static int encx24j600_setlink(struct net_device *dev, u8 autoneg, u16 speed,
689 			      u8 duplex)
690 {
691 	struct encx24j600_priv *priv = netdev_priv(dev);
692 	int ret = 0;
693 
694 	if (!priv->hw_enabled) {
695 		/* link is in low power mode now; duplex setting
696 		 * will take effect on next encx24j600_hw_init()
697 		 */
698 		if (speed == SPEED_10 || speed == SPEED_100) {
699 			priv->autoneg = (autoneg == AUTONEG_ENABLE);
700 			priv->full_duplex = (duplex == DUPLEX_FULL);
701 			priv->speed = (speed == SPEED_100);
702 		} else {
703 			netif_warn(priv, link, dev, "unsupported link speed setting\n");
704 			/*speeds other than SPEED_10 and SPEED_100 */
705 			/*are not supported by chip */
706 			ret = -EOPNOTSUPP;
707 		}
708 	} else {
709 		netif_warn(priv, link, dev, "Warning: hw must be disabled to set link mode\n");
710 		ret = -EBUSY;
711 	}
712 	return ret;
713 }
714 
715 static void encx24j600_hw_get_macaddr(struct encx24j600_priv *priv,
716 				      unsigned char *ethaddr)
717 {
718 	unsigned short val;
719 
720 	val = encx24j600_read_reg(priv, MAADR1);
721 
722 	ethaddr[0] = val & 0x00ff;
723 	ethaddr[1] = (val & 0xff00) >> 8;
724 
725 	val = encx24j600_read_reg(priv, MAADR2);
726 
727 	ethaddr[2] = val & 0x00ffU;
728 	ethaddr[3] = (val & 0xff00U) >> 8;
729 
730 	val = encx24j600_read_reg(priv, MAADR3);
731 
732 	ethaddr[4] = val & 0x00ffU;
733 	ethaddr[5] = (val & 0xff00U) >> 8;
734 }
735 
736 /* Program the hardware MAC address from dev->dev_addr.*/
737 static int encx24j600_set_hw_macaddr(struct net_device *dev)
738 {
739 	struct encx24j600_priv *priv = netdev_priv(dev);
740 
741 	if (priv->hw_enabled) {
742 		netif_info(priv, drv, dev, "Hardware must be disabled to set Mac address\n");
743 		return -EBUSY;
744 	}
745 
746 	mutex_lock(&priv->lock);
747 
748 	netif_info(priv, drv, dev, "%s: Setting MAC address to %pM\n",
749 		   dev->name, dev->dev_addr);
750 
751 	encx24j600_write_reg(priv, MAADR3, (dev->dev_addr[4] |
752 			     dev->dev_addr[5] << 8));
753 	encx24j600_write_reg(priv, MAADR2, (dev->dev_addr[2] |
754 			     dev->dev_addr[3] << 8));
755 	encx24j600_write_reg(priv, MAADR1, (dev->dev_addr[0] |
756 			     dev->dev_addr[1] << 8));
757 
758 	mutex_unlock(&priv->lock);
759 
760 	return 0;
761 }
762 
763 /* Store the new hardware address in dev->dev_addr, and update the MAC.*/
764 static int encx24j600_set_mac_address(struct net_device *dev, void *addr)
765 {
766 	struct sockaddr *address = addr;
767 
768 	if (netif_running(dev))
769 		return -EBUSY;
770 	if (!is_valid_ether_addr(address->sa_data))
771 		return -EADDRNOTAVAIL;
772 
773 	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
774 	return encx24j600_set_hw_macaddr(dev);
775 }
776 
777 static int encx24j600_open(struct net_device *dev)
778 {
779 	struct encx24j600_priv *priv = netdev_priv(dev);
780 
781 	int ret = request_threaded_irq(priv->ctx.spi->irq, NULL, encx24j600_isr,
782 				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
783 				       DRV_NAME, priv);
784 	if (unlikely(ret < 0)) {
785 		netdev_err(dev, "request irq %d failed (ret = %d)\n",
786 			   priv->ctx.spi->irq, ret);
787 		return ret;
788 	}
789 
790 	encx24j600_hw_disable(priv);
791 	encx24j600_hw_init(priv);
792 	encx24j600_hw_enable(priv);
793 	netif_start_queue(dev);
794 
795 	return 0;
796 }
797 
798 static int encx24j600_stop(struct net_device *dev)
799 {
800 	struct encx24j600_priv *priv = netdev_priv(dev);
801 
802 	netif_stop_queue(dev);
803 	free_irq(priv->ctx.spi->irq, priv);
804 	return 0;
805 }
806 
807 static void encx24j600_setrx_proc(struct kthread_work *ws)
808 {
809 	struct encx24j600_priv *priv =
810 			container_of(ws, struct encx24j600_priv, setrx_work);
811 
812 	mutex_lock(&priv->lock);
813 	encx24j600_set_rxfilter_mode(priv);
814 	mutex_unlock(&priv->lock);
815 }
816 
817 static void encx24j600_set_multicast_list(struct net_device *dev)
818 {
819 	struct encx24j600_priv *priv = netdev_priv(dev);
820 	int oldfilter = priv->rxfilter;
821 
822 	if (dev->flags & IFF_PROMISC) {
823 		netif_dbg(priv, link, dev, "promiscuous mode\n");
824 		priv->rxfilter = RXFILTER_PROMISC;
825 	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
826 		netif_dbg(priv, link, dev, "%smulticast mode\n",
827 			  (dev->flags & IFF_ALLMULTI) ? "all-" : "");
828 		priv->rxfilter = RXFILTER_MULTI;
829 	} else {
830 		netif_dbg(priv, link, dev, "normal mode\n");
831 		priv->rxfilter = RXFILTER_NORMAL;
832 	}
833 
834 	if (oldfilter != priv->rxfilter)
835 		kthread_queue_work(&priv->kworker, &priv->setrx_work);
836 }
837 
838 static void encx24j600_hw_tx(struct encx24j600_priv *priv)
839 {
840 	struct net_device *dev = priv->ndev;
841 
842 	netif_info(priv, tx_queued, dev, "TX Packet Len:%d\n",
843 		   priv->tx_skb->len);
844 
845 	if (netif_msg_pktdata(priv))
846 		dump_packet("TX", priv->tx_skb->len, priv->tx_skb->data);
847 
848 	if (encx24j600_read_reg(priv, EIR) & TXABTIF)
849 		/* Last transmition aborted due to error. Reset TX interface */
850 		encx24j600_reset_hw_tx(priv);
851 
852 	/* Clear the TXIF flag if were previously set */
853 	encx24j600_clr_bits(priv, EIR, TXIF);
854 
855 	/* Set the data pointer to the TX buffer address in the SRAM */
856 	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
857 
858 	/* Copy the packet into the SRAM */
859 	encx24j600_raw_write(priv, WGPDATA, (u8 *)priv->tx_skb->data,
860 			     priv->tx_skb->len);
861 
862 	/* Program the Tx buffer start pointer */
863 	encx24j600_write_reg(priv, ETXST, ENC_TX_BUF_START);
864 
865 	/* Program the packet length */
866 	encx24j600_write_reg(priv, ETXLEN, priv->tx_skb->len);
867 
868 	/* Start the transmission */
869 	encx24j600_cmd(priv, SETTXRTS);
870 }
871 
872 static void encx24j600_tx_proc(struct kthread_work *ws)
873 {
874 	struct encx24j600_priv *priv =
875 			container_of(ws, struct encx24j600_priv, tx_work);
876 
877 	mutex_lock(&priv->lock);
878 	encx24j600_hw_tx(priv);
879 	mutex_unlock(&priv->lock);
880 }
881 
882 static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
883 {
884 	struct encx24j600_priv *priv = netdev_priv(dev);
885 
886 	netif_stop_queue(dev);
887 
888 	/* save the timestamp */
889 	netif_trans_update(dev);
890 
891 	/* Remember the skb for deferred processing */
892 	priv->tx_skb = skb;
893 
894 	kthread_queue_work(&priv->kworker, &priv->tx_work);
895 
896 	return NETDEV_TX_OK;
897 }
898 
899 /* Deal with a transmit timeout */
900 static void encx24j600_tx_timeout(struct net_device *dev)
901 {
902 	struct encx24j600_priv *priv = netdev_priv(dev);
903 
904 	netif_err(priv, tx_err, dev, "TX timeout at %ld, latency %ld\n",
905 		  jiffies, jiffies - dev_trans_start(dev));
906 
907 	dev->stats.tx_errors++;
908 	netif_wake_queue(dev);
909 }
910 
911 static int encx24j600_get_regs_len(struct net_device *dev)
912 {
913 	return SFR_REG_COUNT;
914 }
915 
916 static void encx24j600_get_regs(struct net_device *dev,
917 				struct ethtool_regs *regs, void *p)
918 {
919 	struct encx24j600_priv *priv = netdev_priv(dev);
920 	u16 *buff = p;
921 	u8 reg;
922 
923 	regs->version = 1;
924 	mutex_lock(&priv->lock);
925 	for (reg = 0; reg < SFR_REG_COUNT; reg += 2) {
926 		unsigned int val = 0;
927 		/* ignore errors for unreadable registers */
928 		regmap_read(priv->ctx.regmap, reg, &val);
929 		buff[reg] = val & 0xffff;
930 	}
931 	mutex_unlock(&priv->lock);
932 }
933 
934 static void encx24j600_get_drvinfo(struct net_device *dev,
935 				   struct ethtool_drvinfo *info)
936 {
937 	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
938 	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
939 	strlcpy(info->bus_info, dev_name(dev->dev.parent),
940 		sizeof(info->bus_info));
941 }
942 
943 static int encx24j600_get_link_ksettings(struct net_device *dev,
944 					 struct ethtool_link_ksettings *cmd)
945 {
946 	struct encx24j600_priv *priv = netdev_priv(dev);
947 	u32 supported;
948 
949 	supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
950 			 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
951 			 SUPPORTED_Autoneg | SUPPORTED_TP;
952 
953 	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
954 						supported);
955 
956 	cmd->base.speed = priv->speed;
957 	cmd->base.duplex = priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
958 	cmd->base.port = PORT_TP;
959 	cmd->base.autoneg = priv->autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE;
960 
961 	return 0;
962 }
963 
964 static int
965 encx24j600_set_link_ksettings(struct net_device *dev,
966 			      const struct ethtool_link_ksettings *cmd)
967 {
968 	return encx24j600_setlink(dev, cmd->base.autoneg,
969 				  cmd->base.speed, cmd->base.duplex);
970 }
971 
972 static u32 encx24j600_get_msglevel(struct net_device *dev)
973 {
974 	struct encx24j600_priv *priv = netdev_priv(dev);
975 
976 	return priv->msg_enable;
977 }
978 
979 static void encx24j600_set_msglevel(struct net_device *dev, u32 val)
980 {
981 	struct encx24j600_priv *priv = netdev_priv(dev);
982 
983 	priv->msg_enable = val;
984 }
985 
986 static const struct ethtool_ops encx24j600_ethtool_ops = {
987 	.get_drvinfo = encx24j600_get_drvinfo,
988 	.get_msglevel = encx24j600_get_msglevel,
989 	.set_msglevel = encx24j600_set_msglevel,
990 	.get_regs_len = encx24j600_get_regs_len,
991 	.get_regs = encx24j600_get_regs,
992 	.get_link_ksettings = encx24j600_get_link_ksettings,
993 	.set_link_ksettings = encx24j600_set_link_ksettings,
994 };
995 
996 static const struct net_device_ops encx24j600_netdev_ops = {
997 	.ndo_open = encx24j600_open,
998 	.ndo_stop = encx24j600_stop,
999 	.ndo_start_xmit = encx24j600_tx,
1000 	.ndo_set_rx_mode = encx24j600_set_multicast_list,
1001 	.ndo_set_mac_address = encx24j600_set_mac_address,
1002 	.ndo_tx_timeout = encx24j600_tx_timeout,
1003 	.ndo_validate_addr = eth_validate_addr,
1004 };
1005 
1006 static int encx24j600_spi_probe(struct spi_device *spi)
1007 {
1008 	int ret;
1009 
1010 	struct net_device *ndev;
1011 	struct encx24j600_priv *priv;
1012 	u16 eidled;
1013 
1014 	ndev = alloc_etherdev(sizeof(struct encx24j600_priv));
1015 
1016 	if (!ndev) {
1017 		ret = -ENOMEM;
1018 		goto error_out;
1019 	}
1020 
1021 	priv = netdev_priv(ndev);
1022 	spi_set_drvdata(spi, priv);
1023 	dev_set_drvdata(&spi->dev, priv);
1024 	SET_NETDEV_DEV(ndev, &spi->dev);
1025 
1026 	priv->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
1027 	priv->ndev = ndev;
1028 
1029 	/* Default configuration PHY configuration */
1030 	priv->full_duplex = true;
1031 	priv->autoneg = AUTONEG_ENABLE;
1032 	priv->speed = SPEED_100;
1033 
1034 	priv->ctx.spi = spi;
1035 	devm_regmap_init_encx24j600(&spi->dev, &priv->ctx);
1036 	ndev->irq = spi->irq;
1037 	ndev->netdev_ops = &encx24j600_netdev_ops;
1038 
1039 	mutex_init(&priv->lock);
1040 
1041 	/* Reset device and check if it is connected */
1042 	if (encx24j600_hw_reset(priv)) {
1043 		netif_err(priv, probe, ndev,
1044 			  DRV_NAME ": Chip is not detected\n");
1045 		ret = -EIO;
1046 		goto out_free;
1047 	}
1048 
1049 	/* Initialize the device HW to the consistent state */
1050 	if (encx24j600_hw_init(priv)) {
1051 		netif_err(priv, probe, ndev,
1052 			  DRV_NAME ": HW initialization error\n");
1053 		ret = -EIO;
1054 		goto out_free;
1055 	}
1056 
1057 	kthread_init_worker(&priv->kworker);
1058 	kthread_init_work(&priv->tx_work, encx24j600_tx_proc);
1059 	kthread_init_work(&priv->setrx_work, encx24j600_setrx_proc);
1060 
1061 	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
1062 					 "encx24j600");
1063 
1064 	if (IS_ERR(priv->kworker_task)) {
1065 		ret = PTR_ERR(priv->kworker_task);
1066 		goto out_free;
1067 	}
1068 
1069 	/* Get the MAC address from the chip */
1070 	encx24j600_hw_get_macaddr(priv, ndev->dev_addr);
1071 
1072 	ndev->ethtool_ops = &encx24j600_ethtool_ops;
1073 
1074 	ret = register_netdev(ndev);
1075 	if (unlikely(ret)) {
1076 		netif_err(priv, probe, ndev, "Error %d initializing card encx24j600 card\n",
1077 			  ret);
1078 		goto out_free;
1079 	}
1080 
1081 	eidled = encx24j600_read_reg(priv, EIDLED);
1082 	if (((eidled & DEVID_MASK) >> DEVID_SHIFT) != ENCX24J600_DEV_ID) {
1083 		ret = -EINVAL;
1084 		goto out_unregister;
1085 	}
1086 
1087 	netif_info(priv, probe, ndev, "Silicon rev ID: 0x%02x\n",
1088 		   (eidled & REVID_MASK) >> REVID_SHIFT);
1089 
1090 	netif_info(priv, drv, priv->ndev, "MAC address %pM\n", ndev->dev_addr);
1091 
1092 	return ret;
1093 
1094 out_unregister:
1095 	unregister_netdev(priv->ndev);
1096 out_free:
1097 	free_netdev(ndev);
1098 
1099 error_out:
1100 	return ret;
1101 }
1102 
1103 static int encx24j600_spi_remove(struct spi_device *spi)
1104 {
1105 	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);
1106 
1107 	unregister_netdev(priv->ndev);
1108 
1109 	free_netdev(priv->ndev);
1110 
1111 	return 0;
1112 }
1113 
1114 static const struct spi_device_id encx24j600_spi_id_table[] = {
1115 	{ .name = "encx24j600" },
1116 	{ /* sentinel */ }
1117 };
1118 MODULE_DEVICE_TABLE(spi, encx24j600_spi_id_table);
1119 
1120 static struct spi_driver encx24j600_spi_net_driver = {
1121 	.driver = {
1122 		.name	= DRV_NAME,
1123 		.owner	= THIS_MODULE,
1124 		.bus	= &spi_bus_type,
1125 	},
1126 	.probe		= encx24j600_spi_probe,
1127 	.remove		= encx24j600_spi_remove,
1128 	.id_table	= encx24j600_spi_id_table,
1129 };
1130 
1131 static int __init encx24j600_init(void)
1132 {
1133 	return spi_register_driver(&encx24j600_spi_net_driver);
1134 }
1135 module_init(encx24j600_init);
1136 
1137 static void encx24j600_exit(void)
1138 {
1139 	spi_unregister_driver(&encx24j600_spi_net_driver);
1140 }
1141 module_exit(encx24j600_exit);
1142 
1143 MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
1144 MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
1145 MODULE_LICENSE("GPL");
1146 MODULE_ALIAS("spi:" DRV_NAME);
1147